President Donald Trump's nationalist trade adviser Peter Navarro has staged a startling comeback.

Last year he nearly disappeared from view when his small operation was subsumed under the White House's National Economic Council, which was headed by his rival, Gary Cohn, the free-trader who was president of Goldman Sachs. Now Cohn's on his way out while Trump is imposing the steel and aluminum tariffs that Navarro advocates.

And he might even take over Cohn's job. It "absolutely" could happen, said Harry Kazianis, a friend of Navarro who is director of defense studies at the Center for the National Interest. "Trump's going to look to Peter and say, 'I know this guy. I can trust him.' "

One factor behind Navarro's surprising resurrection is that Trump has taken renewed interest this year in trade and national security — Navarro's issues — after having focused in 2017 on health care and tax cuts.

The second factor is that Navarro is relentless. He's been in front of TV cameras repeatedly over the past week championing the tariffs.

After losing to Cohn in the White House turf wars, someone else might have packed up and gone home to California. Instead, Navarro kept building the case for stronger action. Even now he's not letting up, said Michael Wessel, a steelworkers representative who speaks with him regularly.

"He is certainly excited about where he is and what's going on because he has worked a long time to get here," Wessel said. "But he's running at warp speed and probably doesn't have much time to think about it."

'Never been afraid'

Free-traders are elbowing one another aside to express their dismay about Navarro's ascendancy — and Navarro welcomes their disdain. Although he holds a Ph.D. in economics from Harvard and taught the subject at the University of California-Irvine Paul Merage School of Business, Navarro accuses his fellow economists of blindly adhering to free-trade principles at the expense of national security.

"The president said very clearly that we can't have a country without steel and aluminum industries, and I totally agree with him," Navarro told Bloomberg TV on Wednesday. Echoing Trump, he added, "All the countries that trade with us are getting the better part of the deal." He also said he is not on the list of candidates to replace Cohn.

Navarro has a monkish demeanor. He's wiry, almost gaunt. Running shoes by the door of his office attest to his habit of running to work. He works long hours, and his closest administration ally is Commerce Secretary Wilbur Ross, a fellow trade nationalist.

Navarro's not-so-secret weapon in the White House turf wars is that he has a lot in common with the president. They're about the same age: Navarro is 68 and Trump 71. Also, neither backs down from a fight. "Peter has always been a contrarian, someone who's never been afraid to defend his views vociferously," said Scott Paul, president of the Alliance for American Manufacturing.

Most important, both Navarro and Trump are former Democrats who feel no compunction to stick to Republican orthodoxy on trade.

Navarro was actually kind of a liberal once. He served in the Peace Corps, surfed, and campaigned against uncontrolled real-estate development in the race for mayor of San Diego in 1992. Now he works for one of the world's most famous developers. One poster for his 1996 congressional race read: "Peter Navarro. The Democrat Newt Gingrich fears most!"

On Wednesday, Navarro heaped praise on his boss and described his own role as that of an enabler.

'Interchangeable parts'

"This is the president's vision. My function, really, as an economist is to try to provide the underlying analytics that confirm his intuition. And his intuition is always right in these matters," Navarro said.

He compared the White House to the successful New England Patriots football team. "The owner, the coach, and the quarterback are all the president. The rest of us are all interchangeable parts."

The interchangeable part labeled Peter Navarro got off to a strong start last year when Trump pulled the U.S. out of negotiations on the 12-nation Trans-Pacific Partnership trade deal, one of his first acts in office.

Navarro also spearheaded the president's "Buy American, Hire American" initiative, which tightens enforcement of federal procurement rules and cracks down on alleged abuse of H-1B visas and other foreign-hiring programs. In April, Trump called Navarro "one of the greats at trying to protect our jobs."